.container{
  width: 80%;
  height: 90vh;
  margin: 0 auto;
  border: 1px solid #d7d1d1;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.content{
  flex: 1;
  overflow-y: scroll;
}
.user{
  text-align: right;
}
.item{
  margin: 10px 0;
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.1);
  padding: 10px;
  border-radius: 8px;
}
.input{
  display: flex;
}
.input input{
  flex: 1;
  font-size: 16px;
  padding: 5px 20px;
}
.input button{
  font-size: 16px;
  padding: 5px 20px;
  margin-left: 20px;
}